题解 | 统计复旦用户8月练题情况
select up.device_id,up.university,count(*) as question_cnt,sum(if(qpd.result='right', 1, 0)) as right_question_cnt from user_profile as up inner join question_practice_detail as qpd on qpd.device_id=up.device_id and month(qpd.date)=8 and up.university='复旦大学' group by up.device_id
查看12道真题和解析